How to show at listbox2 value by select value from listbox1 (by id) c#

How to show at ListBox value by select value from listbox1 (by id), at asp.net c#...

example:

listbox1 (car name) :  Fiat , subaro, honda

listbox2 (car type..after fiat selected at box1) : punto sx, punto gx. punto blab开发者_JS百科la-x (...)

listbox3 (car year...after type selected) : 2000-2002 (....)

listbox4 (items for the car that selected at lstbox1 2 and 3 .. : volta, wheel (...)

i have database (sql) with tables: CarName, CarType , CarYear, Items

thanks!

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An easy way is to bind the second listbox to a var in the selectedindexchanged event of the first listbox. Example (using dropdownlistboxes in this case):

protected void DropDownList1_SelectedIndexChanged(object sender, EventArgs e)
{
    var x =
        [LINQ query here]
    DropDownList2.DataSource = x;
    DropDownList2.DataTextField = "[fieldname]";
    DropDownList2.DataValueField = "ID";
    DropDownList2.DataBind();
}

If you know how to write the query and assign the correct field to the DataTextField (the one that will show up in the 2nd listbox) you're all set.

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Try this AjaxControlToolkit control.

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Try the SelectedIndexChanged event. Just make sure you have the id in the Tag. Here's an example edited from a recent (WinForms) homework assignment I had:

private void lstCarName_SelectedIndexChanged(object sender, EventArgs e)
{
    if (lstCarName.SelectedItems.Count > 0)
    {
        int CarId = (int)lstKlanten.SelectedItems[0].Tag;
        MakeCarTypeListBox(id);
    }
}

MakeCarTypeListBox could look something like:

private void MakeCarTypeListBox(int carId)
{
    lstCarType.Items.Clear();
    CarType[] carTypes = CarType.CarTypesByCarNameI(carId);
    for (int i = 0; i < carTypes.Length; i++)
    {
        ListViewItem item = new ListViewItem(carTypes[i].Id.ToString());
        item.SubItems.Add(carTypes[i].CarTypeName);
        item.Tag = carTypes[i].Id;

        lstDetail.Items.Add(item);
    }
}

Bear in mind that I used WinForms and home-made entity classes though, so your code will probably be somewhat different...